The Rule of 20

The Rule of 20 is one of the techniques you will learn when learning how to bid in bridge.  It is used in just one situation – when deciding if your hand is suitable for opening the bidding.  As a general rule, a hand should contain 12 or more high card points (HCP) if you are going to open the bidding.  Sometimes, though, you might want to open the bidding with a hand that contains fewer points.  This is when you use The Rule of 20 – its purpose is to decide if a hand with fewer than 12 points is suitable for opening.

Using The Rule of 20

Start by adding up your high card points.  Then add to that the length of your two longest suits. If the total is 20 or more then your hand passes The Rule of 20 and you can open the bidding.


Hand 1

(spades) A  7 5 4
(hearts)  6 5 3
(diamonds) A K 8 5 3
(clubs) 9

Hand 1 has 11 HCPs. The lengths of the two longest suits are five and four. This makes a total of 20, so the hand is suitable for opening.

Hand 2

(s) 8 3
(h) A Q 9 5 4
(d) K J 6 4 2
(c) 5

Hand 2 has only 10 points but has two 5 card suits. So adding the points (10) to the length of the two longest suits (10) gives a total of 20. It passes the Rule of 20 so we can open with one of a suit.

Hand 3

(s) Q J 4
(h) A 7
(d) 10 7 5
(c) K J 8 6 3

Hand 3 has 11 points, but adding in the length of the two longest suits (5 + 3) only gives a total of 19.  This hand doesn’t pass the Rule of 20 and so isn’t suitable for opening.